Sometimes we had to make small brass plates with lettering on it. These days you can go to any number of places online and get something made up, more often in plastic or on special engraving sheet. Engraving sheet has a couple of layers of different colours. Say you wanted red letters on a black background you would buy a sheet that was black on top with red on the next layer. The letters would be cut out with a pantograph and deep enough so that the red underlayer showed through.
We nearly bought a pantograph but foolishly at the last minute decided against it. A mistake. So if we wanted a brass label this is how we went about making one.
What you need.
- Some brass sheet or plate, depending on how thick you wanted it.
- Ferric chloride. You can buy it as a solution but we used to buy it as granules and mix it with warm water as per the instructions.
- A suitable sized plastic box.
- Gloves.
- We used to buy small vinyl letters that came on a sheet. You rubbed them off and stuck them to the brass to form the words you want. They were made by a company called Letraset. Not sure if they are made any more. I am sure you can get other makes. Below a picture of a sheet of letters.
What you are going to do.
- The idea is that you mark off any areas that you do not want to be etched. The back and sides of your sheet and the lettering you want. It is marked off with anything that will resist the etching solution. Stick on your letters, Then put a thin coat of vaseline on the back and the sides of the plate. I think you can even write your words with a felt-tipped permanent marker pen or use it to mark off the areas you do not want to be etched. Never tried it myself but I have been told it works. You could use nail varnish, basically anything that will resist the ferric chloride. The plate is then dipped into the ferric chloride and left for a time. How long will depend on how strong you made the solution or how deep you want the etching to be.
To do.
- Cut your brass sheet/plate to the size of your label.
- Clean up the edges with a file and polish them then polish the front face.
- Clean it very well in alcohol or a degreaser to remove any finger marks. Having done this only handle it with surgical gloves to keep it clean and grease free.
- Apply your lettering.
- Put your chosen etch resist onto all the other parts you do not want to be etched, back and sides. In summary, you now have the back and sides resistant to the ferric chloride and under the lettering.
- Place it in the solution.
- Keep the dish moving to prevent air bubbles forming on the plate and spoiling the finish by resisting the etch solution.
- Take it out now and again to check the progress. Do not leave it too long because the ferric chloride will undercut the lettering.
- When you are happy with the depth of etching remove the plate and wash it off under the tap, Clean off the etch resist coating and the lettering.
- Tip the ferric chloride into a labelled plastic bottle, it can be used a number of times.
- Carefully polish the whole thing.
- Job done.
- Note. You can, of course, do it a different way and rather than having the raised letter, you will get from the above process have your lettering go down into the brass. Stick on your vinyl letters, and cover everything with etch resist. If the permanent marker idea works that would be the easiest. Then carefully peel off the letters and dip in the same way. This way the ferric chloride will etch where the letters were stuck and nowhere else. This way you will get lettering that goes into the brass rather than raised up from it.
- You can leave the letters on, carefully clean off the resist then spray paint the plate and when the paint is dry peel off the letters and polish them.
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